slant is running hot

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jamesdart

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rather than throw parts at it id like some ideas. i really dont want to buy a new rad for it, but i think that is the culprit. help me rule out anything else before dropping the cash. car will sit and idle maybe 20 min and start getting hot, it will just keep climbing and eventually boil over. i would say you could drive it the same amount of time. i pulled the center of the thermostat out as i thought it stuck shut. it didnt seem to do much. it was a 195 t stat. i put a new 160 in. seems to run longer. i flushed the cooling system out several times. an awful lot of rusty water coming out. i ran a gallon of vinegar through it hearing that is supposed to clean out the rust. im not getting good heat inside the car even when the temp is up there. i ran the garden hose through the heater core too, maybe that is unrelated. withthe cap off the rad you could see the water wasnt flowing that well down the tubes you could see through the opening. i ran a wire through them and they seemed to drain better. but that is only a handful of tubes. i got a price o na new rad for 270, more than i want to spend. this car was supposed to be a big block swap. i was thinking of buying an aluminum rad and making it work, but i dont want to buy anything if the rad is not the culprit. i do not have a fan shroud, fan is about 1 1/2" from the rad. it has only been in the 40s to 60s here temp is no reason to run hot. im not getting water in the oil or steam out the exhaust but im really hoping i dont have a blown head gasket in a way that a cylinder is blowing into the coolant?
 
Im going with either the radiator or heater core.
Or the combination of the two.
 
It just sounds like a typical clogged up mopar radiator to me. I have seen them do that same kind of crap over and over again. I flush mine out every year NO MATTER WHAT!!!!! I dont care if it needs it or not. It probably just got REALLY clogged up. You will more than likely have to do a really serious flush on it. I hope someone will chime in and give you a good product to use that will work on a heavy clogging problem. I dont really know what to suggest because I've never let mine get that bad before. I've seen other people have to deal with it a lot though.
 
How about a water pump and do a good engine flush.
The kind that you let sit in the engine. and I am assuming your oil pump is doing its job getting oil to the top.
 
the last annual inspection on ths car was 1981 so to the best of my knowledge it has been off the road for a really long time. i think the prev owner was trying to get it road worthy as it had a few new parts when i got it. will a heater core make a car overheat? with engine swaps i never bothered with stock rads just went right for the cheap aluminum ones. im thinking of pulling the top tank off and making something to clean all he tubes out. as for the water pump, i was thinking of pulling iot off to inspect it. think is possible the blades are gone?
 
NAPA engine flush and follow instructions to the T. It does work, I seen some nasty stuff come out of my 63 valiant I had, It sat for over 7 years.
I got it up to temp and let it set, Then I removed the lower radiator hose and let it drain out.
 
the last annual inspection on ths car was 1981 so to the best of my knowledge it has been off the road for a really long time. i think the prev owner was trying to get it road worthy as it had a few new parts when i got it. will a heater core make a car overheat? with engine swaps i never bothered with stock rads just went right for the cheap aluminum ones. im thinking of pulling the top tank off and making something to clean all he tubes out. as for the water pump, i was thinking of pulling iot off to inspect it. think is possible the blades are gone?
No, a heater core can be bypassed by putting the two hoses together.
and yes the blades can be wore and rotted so you wont get good flow.
 
the last annual inspection on ths car was 1981 so to the best of my knowledge it has been off the road for a really long time. i think the prev owner was trying to get it road worthy as it had a few new parts when i got it. will a heater core make a car overheat? with engine swaps i never bothered with stock rads just went right for the cheap aluminum ones. im thinking of pulling the top tank off and making something to clean all he tubes out. as for the water pump, i was thinking of pulling iot off to inspect it. think is possible the blades are gone?

Yes, a heater core can help with over heating. It is part of the system. If the water isnt flowing like it should, then the car will over heat.

Have the radiator rotted out. This will clean the insides out. Rust scale is usually what blocks a radiator up. If it has the org heater core, now would be a good time to replace it. check out www.rockauto.com for a price on one.

Always use distilled water, and I like to add water wetter. The stuff works.
 
Yes, a heater core can help with over heating. It is part of the system. If the water isnt flowing like it should, then the car will over heat.

Have the radiator rotted out. This will clean the insides out. Rust scale is usually what blocks a radiator up. If it has the org heater core, now would be a good time to replace it. check out www.rockauto.com for a price on one.

Always use distilled water, and I like to add water wetter. The stuff works.
Cant he jus bypass the heater core and see what happens ?
 
You didn't mention what year/model you're dealing with, but a brand new radiator for my Swinger from rockauto.com lists for $209, so you might try that if you end up buying a new one.
 
Cant he jus bypass the heater core and see what happens ?

Yes. I've done it on more than one car. It may not be the best option but a circumvented heater core never caused my car to over heat, drove well over a year like that with no problems. Having a good heater core however does increase the water coolant loop though and should be replaced if possible. Just my .02
 
Rad is mostly plugged and block and core is full of crud.

Get new V8 rad and shroud and install new water pump....after you reverse flush engine and heater core several times. That way you get a majority of the crud out before you install the new stuff.
 
i blasted the heater core out with the hose and clean water came out the other end so im kind of thinking the heat deal has something to do with the box not the heater core.
 
James, check out my fun....The thread has some before and after pics of what a typical clogged mopar rad looks like.
http://www.forabodiesonly.com/mopar/showthread.php?t=43837

Had a problem with the car overheating at hwy speed but not at idle ( with a 22" rad ).
Fixed it with about $20 worth of supplies from the hole depot and about a whole afternoon of cussing....what can I say...I have more time than money :)
 
that is exactly what i was thinking of doing, but decided i better try my luck flushing it some more today. i cant believe how much more crap is coming out since last time when i tried the vinegar and a real strong degreaser. one or the other must have really loosened the crap up. i want to make sure i know what is wrong before i buy a single thing. i have issues with buying unneccesary parts. so what is this "fish tape" i always thought those were for pulling wire? guess im thinking of something else.
 
You also mentioned no heat in the car with the temp up.

That is one of the first signs of a bad heater core.

Yes you can by-pass it, but then no heat. Depends if you want heat or not.
 
James
Yellow Dart Dave is Spot on, As are others. Remember this is also a BIG problem when you rebuild an engine. You loosen up the crud and put your new rad in and "poof" plugged new rad.
Do ALL your flushing now. And then get your new or rebuilt rad and put it in.
Frank
 
James, the fish tape is correct... after I pulled the top tank off I had the problem of finding something that was rigid enough to push out the crap and thin enough to fit...enter the fish tape...I did have to cut then end off to make it fit thru the tiny passages but it worked like a charm

As for the heater core being plugged up...I agree that it is an indicator of how bad the crud in the system is, AND if the heater core is plugged, then so is the rad.....

When you do get a new radiator..check into installing a filter in the upper hose.
Something like this. (for the sake of not clogging up a new part)
http://neptune.spacebears.com/cars/stories/sctefba.html
 
ahhh, laugh if you will, i filled the cooling system with a mix of 50/50 purple power and water ran it withthe cap off let it get hot. of coarse it wa smaking a sudsy mess, i flushed it out and ran it again. nothing real significant came out, until i ran it up to temp at high idle. i flushed it out with just water and kept refilling and letting it get warm, draining the system once it got warm, the first few times, straight black funk came out. not even rust color. it was black. i blasted the heater core out again and it seems to be good now. i flushed it about 8 times. rad drains much faster now and the temp seems to be holding pretty low. we'll see.
 
i would by pass the heater core as a temp mesure to check and see if that is the problem or not. in most cases its the radiator, i have had 7 slant 6 cars and in 4 out of 5 overheating issues it was a bad rad.
 
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